Cloud-based marketing is becoming increasingly integrated with Internet of Things (IoT) devices. One such cloud-based marketing technique, sometimes referred to as “digital signage,” employs display screens that deliver real-time, targeted advertising messages, based on data provided from IoT device sensors. For example, raincoats or umbrellas may be displayed if sensors detect that it is raining. So, in some respects, the digital signage is intelligent. Marketers can prepare both content and rules, to govern the display of such content based on sensor data. However, it can be difficult to develop and field test such systems, because the marketer does not necessarily have direct control over, or knowledge of, the IoT device sensor messages. In order to test the digital signage, the IoT device sensors need to be physically acted upon to generate a particular type or range of data values that are of interest in a given application, to trigger the generation of associated advertising content. Testing of the digital signage applications therefore requires certain conditions to exist so as to trigger the IoT device sensors to output a message to the digital signage application. In other words, for example, to test a given proximity-based or temperature-based application, the marketer would need to move in front of a proximity sensor to trigger a proximity event, or heat a temperature sensor to trigger a warm temperature event, which is neither convenient nor practical.